Roof-jack.



B vP. DARNALL.

ROOF JACK.

APPLICATION FILED AUG. 26, 1912.

1,054,091 Patented Feb. 25, 1913.

UNITED STATES PATENT OFFTCE.

BENJAMIN P. DARNALL, OF SAN ANTONIO, TEXAS.

ROOF-JACK.

To all whom. 2'25 may concern:

Be it known that I, BENJAMIN P. DAR- NALL, a citizen of the UnitedStates, residing in San Antonio, in the county of Bexar and State ofTexas, have invented certain new and useful Improvements in Roof-Jacks,of which the following is a specification.

My invention relates to acks or brackets used to support planks orrunning-boards to provide a scaffold for the use of roofers, tinners,carpenters, etc., and the object of my invention is to provide a jack ofthis class which is simple in construction, may be easily applied to thestanding seams of tin roofs and which will firmly support the plank orrunningboard.

In carrying out my invention I form the jack with a slotted body portionadapted to straddle the standing seam and which is provided on its upperend with a laterally projecting arm adapted to receive and support theplank or runningboard.

The body portion of the jack carries a cam lever adapted to engage theseam and this lever cooperates with an abutment on the body of the clampopposite the lever. The plank-supporting arm is slotted to receive theseam and carries an arched brace, the outer ends of which are adapted torest on the roof and steady the jack.

In the accompanying drawings, Figure 1 is a perspective view of a roofwith my improved jacks attached thereto and supporting a running-board.Fig. 9. is a perspective view on an enlarged scale of the jack, therunning-board or plank being shown by dotted lines. Fig. 3 shows atransverse section on the line 33 of Fig. 2.

In Fig. 1 a tin roof is indicated at A and the standing seams thereof ata.

B indicates a plank or running-board resting on the jacks. It will beunderstood that a pluralitytwo or moreof jacks are employed to supportthe plank and that they may be secured to the seams of the roof at anydesired elevation and can be moved from place to place as required. Theworkmen may stand on the scaifold thus constructed or they may rest aladder thereon.

Specification of Letters Patent.

Application filed August 26, 1912.

Patented Feb. 25,1913. Serial No. 717,085.

The jack comprises a body portion 0 having an arm 0 at its lower endwhich projects outward and is relatively short, being in length onlyslightly greater than the height of the seam. A longer arm C projectsoutward from the body portion of the jack at its upper end and is ofsufiicient length to receive and support the plank or running-board. Theend of the arm is preferably bent at c in such manner as to bear againstthe front edge of the plank as shown in Fig. 1. The body portion 0, arm0, and arm C are all slotted as shown, said slot being adapted toreceive the standing seam a of the tin roof. It will be observed thatthe body portion is slotted from end to end, while the arms 0 and C arenot slotted throughout, there being solid end portions m, 00 to hold thetwo parts of the arms and body together.

At D on one side of the slot an arch or bend is made in the body portionto provide an abutment against which the seam is pressed by a cam leverE pivoted to the body on the opposite side thereof.

F indicates an arched brace secured to the arm 0 and adapted to rest atits outer ends on the roof and steady the jack. The jack is applied tothe roof by sliding it over a seam while the cam lever is open and thenturning the lever until the cam e thereon firmly engages the seam andpresses it against the abutment D. Preferably the arch and the cam areserrated or roughened as shown in order that they may take a firmer gripand preferably the cam is so formed and so applied that'the weight onthe jack will tend to move the cam into closer engagement with the seamwhereby any tendency for the jack to slip on the seam is avoided.

I claim as my invention:

1. A jack for roof scaffolds, comprising a slotted body portion adaptedto receive the roof seam, a plank-supporting arm, an abutment on oneside of the slot and a cam lever on the opposite side thereof adapted topress the seam against the abutment.

2. A jack for roof scaffolds, comprising a slotted body portion adaptedto receive the roof seam, a slotted plank-supporting arm, In testimonywhereof I have hereunto an abutment on one slde 0f the slot, a camsubscribed my name. lever 011 the opposite side thereof adapted to pressthe seam against the abutment and an DARNALL' arched brace secured tothe plank-support- Vitnesses:

111g arm and adapted to rest 011 the roof and B. A. GREATHOUSE,

thus steady the jack. E. P. LIPSCOMB.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents. Washington, I). G.

